The present invention relates to a method of processing a multi-page document, the method including the steps of receiving scan images from optically scanning a sequence of pages of the multi-page document, and processing the scan images to generate a file of page images corresponding to original pages of the multi-page document.
The present invention also relates to a computer program product for processing a multi-page document.
The present invention further relates to a document processing system comprising a scanner unit for generating scan images from optically scanning a sequence of pages of a multi-page document, a local user interface unit, and an image processor unit for processing the scan images to generate page images corresponding to original pages of the multi-page document.
When large documents must be scanned in for archiving purposes, it is quite important that all pages of the document are scanned faultlessly, since when scan errors are later detected, the original documents may no longer be available. Therefore, it is necessary to check each scan image for quality. However, checking the quality of each scan image requires much time and effort and poses an undue burden on the personnel performing the scan job. Moreover, checking large numbers of images is boring and error-prone.
One way of circumventing the human checking process is using an automated system that automatically checks each new scan image and if possible corrects faulty images by relevant image processing techniques. A scan image that does not conform to a predetermined quality standard is hereinbelow called an “outlier”.
Such a method is known from patent application WO98/09427, which describes an arrangement and a method for ensuring quality during scanning or copying. The method includes the steps of feeding in the page(s) that are to be scanned and checking the quality of the scan images in a sequence of steps, including a check of outer characteristics which is performed with respect to skew, double-feeding/overlapping, deviating shape, and geometric deformation; a check of so-called inner quality of the contents of the page, and a check of the information content quality. In each step, the measured quality is compared to a quality limit. If the measured quality is according to the limit or better, an automatic adjustment of the scan image is performed if necessary, after which the scan image is added to the scan file. If the measured quality is below the limit, the operator is requested to re-feed the page for re-scanning.
In the known system, the quality check is made on the basis of fixed, pre-programmed quality limits that may not always fit with the practical situation. If the check is negative, there is no other option than re-scanning, which forces the operator to re-feed the document. It may, however, occur that a rejected scan image is in fact still acceptable, or can be made acceptable by a small adjustment, and that re-scanning is not at all necessary.